The present invention relates to a semiconductor device, for example, relates to one capable of being preferably utilized for a semiconductor device including a vertical MISFET (Metal Insulator Semiconductor Field Effect Transistor).
A transistor for high-power use that can treat electric power of several watts or more is referred to as a power transistor, and, as such power transistors, there are transistors having various structures such as a power MISFET. Furthermore, as the power MISFET, a so-called vertical MISFET in which an electric current flows in the thickness direction of a semiconductor substrate and a so-called horizontal MISFET in which an electric current flows along the upper surface of a semiconductor substrate are used.
As the above-described vertical MISFET, there exist a vertical MISFET of a trench gate type having a gate electrode embedded in the inside of a gate trench and a vertical MISFET of a planar type having a gate electrode formed along the upper surface of a semiconductor substrate. Among these, the vertical MISFET of a trench gate type is advantageous as compared with the vertical MISFET of a planar type in that a so-called parasitic JFET (Junction Field Effect Transistor) resistance component can be made smaller, and the development of it is being advanced.
In Published Japanese translation of PCT patent application No. 2010-534921 (Patent Literature 1), a vertical MISFET of a trench gate type including a drain region, a body region, a gate region, a gate insulator region, a source region, and a source/body contact plug is disclosed. In the vertical MISFET disclosed in Patent Literature 1, a body contact region is disposed in the body region adjacent to the source/body contact plug.